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FAIR VALUE MEASUREMENTS | 3 Months Ended
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Mar. 31, 2012
FAIR VALUE MEASUREMENTS [Abstract] |
FAIR VALUE MEASUREMENTS | FAIR VALUE MEASUREMENTS We segregate the inputs used in measuring fair value into three levels: Level 1, defined as observable inputs such as quoted prices in active markets; Level 2, defined as inputs other than quoted prices in active markets that are either directly or indirectly observable; and Level 3, defined as unobservable inputs in which little or no market data exists. We consider counterparty credit risk and our own credit risk in the determination of all estimated fair values. Product Imbalances We value our assets and liabilities related to product imbalances using quoted market prices in active markets as of the reporting date. Interest Rate Swaps We estimate the fair value of both our fixed-to-floating and forward-starting interest rate swaps using discounted cash flows, which use observable inputs such as time to maturity and market interest rates. Commodity Derivatives We base the fair value of certain of our commodity derivative instruments on quoted prices on an exchange; accordingly, we include these in Level 1 of the fair value hierarchy. We also have derivative instruments for which we determine fair value using industry pricing services and other observable inputs, such as quoted prices on an exchange for similar derivative instruments. Therefore, we include these derivative instruments in Level 2 of the fair value hierarchy. We have consistently applied these valuation techniques in all periods presented. See Note 7. Derivatives and Risk Management Activities for a discussion of our derivative instruments. The following assets and liabilities are measured at fair value:
| March 31, 2012
| Level 1 |  | Level 2 |  | Level 3 |  | Total
| (Thousands of Dollars)
Other current assets: |  |  |  |  |  |  |
Product imbalances | $ | 1,661 |  |  | $ | — |  |  | $ | — |  |  | $ | 1,661 |
Commodity derivatives | 21,880 |  |  | 329 |  |  | — |  |  | 22,209 |
Other long-term assets, net: |  |  |  |  |  |  |
Commodity derivatives | — |  |  | 5,377 |  |  | — |  |  | 5,377 |
Interest rate swaps | — |  |  | 581 |  |  | — |  |  | 581 |
Accrued liabilities: |  |  |  |  |  |  |
Product imbalances | (200 | ) |  | — |  |  | — |  |  | (200 | )
Commodity derivatives | (13,692 | ) |  | (24,500 | ) |  | — |  |  | (38,192 | )
Interest rate swaps | — |  |  | (9,796 | ) |  | — |  |  | (9,796 | )
Other long-term liabilities: |  |  |  |  |  |  |
Commodity derivatives | — |  |  | (6,539 | ) |  | — |  |  | (6,539 | )
Interest rate swaps | — |  |  | (11,221 | ) |  | — |  |  | (11,221 | )
Total | $ | 9,649 |  |  | $ | (45,769 | ) |  | $ | — |  |  | $ | (36,120 | )
| December 31, 2011
| Level 1 |  | Level 2 |  | Level 3 |  | Total
| (Thousands of Dollars)
Other current assets: |  |  |  |  |  |  |
Product imbalances | $ | 2,117 |  |  | $ | — |  |  | $ | — |  |  | $ | 2,117 |
Commodity derivatives | 10,282 |  |  | 1,830 |  |  | — |  |  | 12,112 |
Other long-term assets, net: |  |  |  |  |  |  |
Commodity derivatives | — |  |  | 27,084 |  |  | — |  |  | 27,084 |
Interest rate swaps | — |  |  | 2,335 |  |  | — |  |  | 2,335 |
Accrued liabilities: |  |  |  |  |  |  |
Product imbalances | (1,469 | ) |  | — |  |  | — |  |  | (1,469 | )
Commodity derivatives | (5,424 | ) |  | — |  |  | — |  |  | (5,424 | )
Interest rate swaps | — |  |  | (22,009 | ) |  | — |  |  | (22,009 | )
Other long-term liabilities: |  |  |  |  |  |  |
Interest rate swaps | — |  |  | (27,190 | ) |  | — |  |  | (27,190 | )
Total | $ | 5,506 |  |  | $ | (17,950 | ) |  | $ | — |  |  | $ | (12,444 | )
Fair Value of Financial Instruments We recognize cash equivalents, receivables, payables and debt in our consolidated balance sheets at their carrying amount. The fair values of these financial instruments, except for debt, approximate their carrying amounts. The estimated fair value and carrying amount of our debt was as follows:
| March 31, 2012 |  | December 31, 2011
| (Thousands of Dollars)
Fair value | $ | 2,575,496 |  |  | $ | 2,377,565 |
Carrying amount | $ | 2,521,412 |  |  | $ | 2,293,030 |
We estimated the fair value of our publicly-traded senior notes based upon quoted prices in active markets; therefore, we determined the fair value of our publicly-traded senior notes falls in Level 1 of the fair value hierarchy. For our other debt, for which a quoted market price is not available, we estimated the fair value using a discounted cash flow analysis using current incremental borrowing rates for similar types of borrowing arrangements and determined the fair value falls in Level 2 of the fair value hierarchy.

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- Definition The entire disclosure for the fair value of financial instruments (as defined), including financial assets and financial liabilities (collectively, as defined), and the measurements of those instruments as well as disclosures related to the fair value of non-financial assets and liabilities. Such disclosures about the financial instruments, assets, and liabilities would include: (1) the fair value of the required items together with their carrying amounts (as appropriate); (2) for items for which it is not practicable to estimate fair value, disclosure would include: (a) information pertinent to estimating fair value (including, carrying amount, effective interest rate, and maturity, and (b) the reasons why it is not practicable to estimate fair value; (3) significant concentrations of credit risk including: (a) information about the activity, region, or economic characteristics identifying a concentration, (b) the maximum amount of loss the entity is exposed to based on the gross fair value of the related item, (c) policy for requiring collateral or other security and information as to accessing such collateral or security, and (d) the nature and brief description of such collateral or security; (4) quantitative information about market risks and how such risks are managed; (5) for items measured on both a recurring and nonrecurring basis information regarding the inputs used to develop the fair value measurement; and (6) for items presented in the financial statement for which fair value measurement is elected: (a) information necessary to understand the reasons for the election, (b) discussion of the effect of fair value changes on earnings, (c) a description of [similar groups] items for which the election is made and the relation thereof to the balance sheet, the aggregate carrying value of items included in the balance sheet that are not eligible for the election; (7) all other required (as defined) and desired information. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 820 -SubTopic 10 -Section 50 -Paragraph 5 -URI http://asc.fasb.org/extlink&oid=6925170&loc=d3e19296-110258 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 159 -Paragraph 17-22, 27, 28 -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy. Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 825 -SubTopic 10 -Section 50 -Paragraph 10 -URI http://asc.fasb.org/extlink&oid=6947722&loc=d3e13433-108611 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 107 -Paragraph 15C, 15D -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy. Reference 5: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 825 -SubTopic 10 -Section 50 -Paragraph 28 -URI http://asc.fasb.org/extlink&oid=6957238&loc=d3e14064-108612 Reference 6: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 825 -SubTopic 10 -Section 50 -Paragraph 16 -URI http://asc.fasb.org/extlink&oid=6947722&loc=d3e13504-108611 Reference 7: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 107 -Paragraph 15A -Subparagraph a-d -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy. Reference 8: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 825 -SubTopic 10 -Section 50 -Paragraph 21 -URI http://asc.fasb.org/extlink&oid=6947722&loc=d3e13537-108611 Reference 9: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 133 -Paragraph 44A, 44B -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy. Reference 10: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 820 -SubTopic 10 -Section 50 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=6925170&loc=d3e19207-110258 Reference 11: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 825 -SubTopic 10 -Section 50 -Paragraph 30 -URI http://asc.fasb.org/extlink&oid=6957238&loc=d3e14172-108612 Reference 12: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 107 -Paragraph 3, 10, 14, 15 -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy. Reference 13: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 107 -Paragraph 15B -Subparagraph a, b -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy. Reference 14: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 157 -Paragraph 32, 33, 34 -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy. + Details
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